/**
 * SessionManager — Central session lifecycle manager.
 *
 * Responsibilities:
 * 1. Track user activity (mousemove, keydown, click, scroll, touch)
 * 2. Send heartbeat at configurable intervals — only when user has been active
 * 3. Show warning popup after idle timeout
 * 4. Auto-logout after warning countdown expires
 * 5. Sync activity across same-origin tabs via BroadcastChannel so one
 *    active tab keeps other tabs' sessions alive (no cascading logout).
 */
import { SessionCallbacks, SessionConfig } from './sessionTypes';
export declare class SessionManager {
    private config;
    private callbacks;
    /** Timestamps and timers */
    private lastActivityTime;
    /** Timestamp of the last heartbeat fire (initial/periodic/continue/activity). */
    private lastHeartbeatTime;
    /** Set to true whenever user (or any same-origin tab) shows activity. */
    private hadActivitySinceLastHeartbeat;
    private idleCheckInterval;
    private heartbeatInterval;
    private countdownInterval;
    private activityDebounceTimer;
    /** State */
    private running;
    private warningActive;
    private secondsRemaining;
    /** Wall-clock timestamp when the warning countdown began (for background-tab accuracy). */
    private warningStartTime;
    /** Cross-tab activity sync */
    private broadcastChannel;
    /** Bound handlers for event listener cleanup. */
    private boundOnActivity;
    private boundOnVisibilityChange;
    private boundOnBroadcastMessage;
    start(config: Partial<SessionConfig> | undefined, callbacks: SessionCallbacks): void;
    stop(): void;
    continueSession(): void;
    isWarningActive(): boolean;
    getSecondsRemaining(): number;
    private onActivity;
    private onVisibilityChange;
    /** Single source of truth for marking activity locally. */
    private registerActivity;
    private checkIdle;
    private startWarning;
    private startHeartbeat;
    private fireHeartbeat;
    private setupBroadcastChannel;
    private teardownBroadcastChannel;
    private broadcast;
    private onBroadcastMessage;
    private clearTimer;
}